/*
* Copyright (C) 2014 Red Hat, Inc. and/or its affiliates.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jboss.errai.forge.facet.resource;
import org.jboss.errai.forge.facet.base.AbstractBaseFacet;
import org.jboss.errai.forge.xml.ElementFactory;
import org.jboss.errai.forge.xml.XmlParser;
import org.jboss.errai.forge.xml.XmlParserFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import javax.inject.Inject;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import java.io.File;
import java.util.Collection;
import java.util.Map;
import java.util.Map.Entry;
/**
* A base class for modifying XML-based configuration files. Concrete subclasses
* may modify the field {@link AbstractXmlResourceFacet#xmlProperties
* xmlProperties}.
*
* @author Max Barkley <mbarkley@redhat.com>
*/
public abstract class AbstractXmlResourceFacet extends AbstractBaseFacet {
/**
* The properties used when writing to an XML file.
*
* @see {@link OutputKeys}, {@link Transformer}
*/
protected final XPathFactory xPathFactory = XPathFactory.newInstance();
@Inject
protected XmlParserFactory xmlParserFactory;
@Override
public boolean install() {
try {
final File file = getResFile(getRelPath());
final XmlParser xmlParser = xmlParserFactory.newXmlParser(file);
final XPath xPath = xPathFactory.newXPath();
final Map<XPathExpression, Collection<Node>> toInsert = getElementsToInsert(xPath, xmlParser);
final Map<XPathExpression, Node> replacements = getReplacements(xPath, xmlParser);
for (final Entry<XPathExpression, Collection<Node>> entry : toInsert.entrySet()) {
xmlParser.addChildNodes(entry.getKey(), entry.getValue());
}
for (final Entry<XPathExpression, Node> entry : replacements.entrySet()) {
xmlParser.replaceNode(entry.getKey(), entry.getValue());
}
xmlParser.close();
}
catch (Exception e) {
error("Error: failed to add required inheritance to module.", e);
return false;
}
return true;
}
@Override
public boolean isInstalled() {
final String relPath = getRelPath();
if (relPath == null)
// Project config has not been setup yet.
return false;
final File file = getResFile(relPath);
if (!file.exists())
return false;
try {
final XmlParser xmlParser = xmlParserFactory.newXmlParser(file);
final XPath xPath = xPathFactory.newXPath();
final Map<XPathExpression, Collection<Node>> insertedToCheck = getElementsToVerify(xPath, xmlParser);
final Map<XPathExpression, Node> replacedToCheck = getReplacements(xPath, xmlParser);
for (final XPathExpression expression : insertedToCheck.keySet()) {
if (xmlParser.hasNode(expression)) {
for (final Node inserted : insertedToCheck.get(expression)) {
if (!xmlParser.hasMatchingChild(expression, inserted)) {
return false;
}
}
}
else {
return false;
}
}
for (final XPathExpression expression : replacedToCheck.keySet()) {
if (!xmlParser.matches(expression, replacedToCheck.get(expression))) {
return false;
}
}
}
catch (Exception e) {
error("Error occurred while attempting to verify xml resource " + file.getAbsolutePath(), e);
return false;
}
return true;
}
/**
* Get a map of parent nodes to xml fragments used to verify the installation
* of this facet. Nodes in collections in the values of this map must match
* children of the node matching the xpath expression key if this facet is
* installed. If a subclass does not override this, the default value will be
* the map returned by
* {@link AbstractXmlResourceFacet#getElementsToInsert(Document)
* getElementsToInsert}.
*/
protected Map<XPathExpression, Collection<Node>> getElementsToVerify(final XPath xPath,
final ElementFactory elemFactory) throws ParserConfigurationException, XPathExpressionException {
return getElementsToInsert(xPath, elemFactory);
}
@Override
public boolean uninstall() {
final File file = getResFile(getRelPath());
if (!file.exists())
// XXX not sure if this case should return true or false...
return true;
try {
final XmlParser xmlParser = xmlParserFactory.newXmlParser(file);
final XPath xPath = xPathFactory.newXPath();
final Map<XPathExpression, Collection<Node>> insertedNodes = getElementsToInsert(xPath, xmlParser);
final Map<XPathExpression, Node> replacedNodes = getRemovalMap(xPath, xmlParser);
for (final Entry<XPathExpression, Collection<Node>> entry : insertedNodes.entrySet()) {
if (xmlParser.hasNode(entry.getKey())) {
for (final Node inserted : entry.getValue()) {
xmlParser.removeChildNode(entry.getKey(), inserted);
}
}
}
for (final Entry<XPathExpression, Node> entry : replacedNodes.entrySet()) {
if (xmlParser.hasNode(entry.getKey())) {
xmlParser.replaceNode(entry.getKey(), entry.getValue());
}
}
xmlParser.close();
}
catch (Exception e) {
error("Error occurred while attempting to verify xml resource " + file.getAbsolutePath(), e);
return false;
}
return true;
}
/**
* Return a map of xpath expressions of nodes to be replaced to their
* replacements, used when this facet is uninstalled.
*
* @param xPath
* Used to generate {@link XPathExpression XPathExpressions}.
* @param elemFactory
* Used to generate {@link Node Nodes}.
* @return A map of xpath expressions to nodes, used to uninstall this facet.
*/
protected abstract Map<XPathExpression, Node> getRemovalMap(final XPath xPath, final ElementFactory elemFactory)
throws ParserConfigurationException, XPathExpressionException;
protected File getResFile(final String relPath) {
File file = new File(relPath);
if (!file.isAbsolute())
file = new File(getProject().getRootDirectory().getUnderlyingResourceObject(), file.getPath());
return file;
}
/**
* Get DOM nodes to write to an XML configuration file. Concrete subclasses
* should return a map with keys as parent nodes and values as collections of
* nodes that will be merged as children of the the nodes matched by the
* respective key values. Each key should only match a unique node (i.e. this
* is a one-to-many map).
*
* @param elemFactory
* The returned nodes should be created with this.
* @param xPath
* Used to generate xpath expressions for finding nodes to add
* children to.
* @return A map of {@link XPathExpression XPathExpressions} (for finding
* parent nodes), to collections of {@link Node Nodes} to add as
* children.
*/
protected abstract Map<XPathExpression, Collection<Node>> getElementsToInsert(final XPath xPath,
final ElementFactory elemFactory) throws ParserConfigurationException, XPathExpressionException;
/**
* Get a Map of nodes to be replaced in an XML configuration file.
*
* @param elemFactory
* The returned nodes should be created with this.
* @param xPath
* Used to generate xpath expressions for finding nodes to replace.
* @return A map of {@link XPathExpression XPathExpressions} (for finding
* nodes to replace), to replacement {@link Node Nodes} to add as
* children.
*/
protected abstract Map<XPathExpression, Node> getReplacements(final XPath xPath, final ElementFactory elemFactory)
throws ParserConfigurationException, XPathExpressionException;
/**
* Get the relative path of XML file to be configured by this facet. Concrete
* subclasses must return the path (relative to the project root directory) of
* the XML file they are configuring.
*
* @return The path (relative to the project root directory) of an XML
* configuration file.
*/
protected abstract String getRelPath();
}